I'm glad to hear that the kestrel has been seen there. I looked on and off all night (up studying) and only saw the dove. She looks very content there right now trying to sleep at the entrance of the nest box. I was worried that her comfort level at the box might mean that the kestrels were nowhere around. Even though this nest box has been very upsetting at times for me to watch, it has, by the same token been fascinating to see the varying birds try to claim it as theirs.